A conventional collapsible golf cart as shown in FIG. 8, comprises an upper frame 10, a lower frame 20, a connector 30 connecting the two frames 10, 20 in a collapsible way, a club-bag supporter 40 fixed at a lower end of the lower frame 20, a connecting plate 601 and two feet 602, 602 respectively extending from the plate 601 to both sides for holding a wheel 603, a connecting rod 301 respectively connecting the connector 30 with the feet 602, an upper club-bag supporter 70 pivotally fixed on the upper end portion of the upper frame 10, a socket 80 fixed around the top end of the upper frame 10 and a thumb screw 801 screwing through the socket and the wall of the upper frame to immobilize an extensible rod provided to extend through a socket and in the interior of the upper frame to move therein in a telescopic fashion so that the length of the extensible rod can be adjusted for using this golf cart.
This conventional golf cart can become smaller by folding (or swinging) down the upper frame 10 and telescoping the extensible rod 90 inward in the upper frame 10 for storage or become usable for carrying golf clubs by folding (or swing) up the upper frame 10, telescoping the extensible rod 90 outward in the frame 10 and clamping a hinge 302 on the connector 20. The connector 30 has engaging projections 303 in two opposite sides to engage to keep immovable the upper frame 10 and the lower frame 20 in a straight position. However, after a certain period of use, this connector 30 may not function well, becoming rickety or shaky. Besides, a square hole provided in the socket 80 does not fit well with a circular extensible rod 90 so that the golf cart may sway to and fro when it is pulled along by holding a grip fixed at the outer end of the extensible rod 90.